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Discussion Starter #1 (Edited)
Each year I take on a new problem with my 75 and try to learn everything I can about it and how to fix it.
Our C3's have around 2 inches of bump steer or toe in at 3 inches rise.
Say you are flying down the road and go over the crest of a hill and on comming down the other side your car could easily have 2 inches of toe in. On comming down hard on the far side the wheel which is carrying the most weight shoots the car off in a new direction. You immediately corrct, then the suspension compresses and the wheels suddenly toe out causing the car to once agian shoot in a new direction.
This is how you loose control.
I have basically corrected this problem so my car travels throught it's total suspension travel with the wheels pointing staight ahead. It did involve alot of detailing.
I am not asking a questions, just stating a fact and if anyone wants to talk/learn about it start the discussion.
I can discuss brakes, setting up beariings, blower motors, bump steer or rebuilding rear ends, 6 link suspensions, whatever.
I find I drop in here from time to time and the posts very seldom change.
If it involves a C3 lets talk about things to improve it.
Don't mean to rattle any feathers but lets get discussing improvements. I could list tons of improvements but don't want to. I would like to discuss them, and let them come from the discussion.
Once again I am not fishing just wish to share some of my knowledge on making the C3 into a far better handling, power and braking sports car.
Once agian I will not list the changes needed but if they come out of discussions I will gladly take part in them.
 

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Our C3 section has been slow to take off. Maybe because it's summer and everyone is out enjoying their cars... and they only do projects in the winter.

Sounds like you are very knowledgable, and have learned first hand how to make the C3 behave better.

I hope you'll continue to share your wisdom as people post, ask questions, and discuss their issues.

Thanks, bud.:thumbsup:
 

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Discussion Starter #4
Patrick I have done just about everything to the C3. I understand all the working parts, how to modify them to make them last under a 940 horsepower engine. I know how to rework our brakes for superior braking, I even built my own rear axles. I have this knowledge and will gladly share it but I will not just start lecturing on how to do things. I will gladly share but it must be a discussion.
I want to hear others opinions and ideas.
How knows about bump steer? Even what it is? How about hydraboost brakes? How to properly set up wheel bearings? Front and back? Truing up rotors? ETC ETC.
Ask siimple questions and I will help but I will once again not just start rimming off answers.
I want to see this section take off a little. I drop in every day or 2 and nothing changes. No really problems get discussed.
Patrick asking me with your other post to list the changes will not get a response. You introduce the topic, discuss it and I will chim in.
 

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norvalwilhel said:
Patrick asking me with your other post to list the changes will not get a response. You introduce the topic, discuss it and I will chim in.
I didn't do it to get you to respond, I did it to get some blood flowing in the C3 section. ;)
 

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Discussion Starter #6
We need some blood flowing in this section.

Let me start it off. Our brakes suck.
Let the arguements begin?
Better still how can we fix them.
How about hydraboost and shimming the rotor after installing a good set of stainless lined calipers.
 

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i haven't experienced the problem you described. however, i'm not saying it could not happen. i felt the suspensions on the '81's were somewhat nice, especially around curves at a high speed. the car shows no "roll" and it hugs the ground like a magnet.

maybe in a situaltion where someone had to correct the steering while in a curve there may be a problem. what did you recommend to correct this? i've rad that the toe-in and toe-out should not be adjusted to factory specs, but a few degrees off. ( this was stated at vettebrakes.com) i haven't had a reason to adjust any alignment so far, so i'm not sure if doing that helps or not.

my car is still stock and i intend to leave it that way. there are many suspension improvements out there, but i'm not about to sink 1500 bucks into a suspension upgrade on an '81 car. i don't drive it like a bat out of hell anyways, so the stock suspension suits my driving conditions.
 

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Discussion Starter #8
bkuper. YOur car has bump steer too. I test a 2002 mustang GT and it had 3/8th per wheel at 3 inches rise . That's 3/4 inch toe in when the front bumper rises 3 inches.
You will not do better.
The ONLY car that doesn't suffer from bump steer from the factory is the Viper. NO other car is immune.
 

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Discussion Starter #9
mga bump steer doesn't just happen in the curves but it does if the car leans , it happens driving in a straight line down the road and your car has bump steer, you just don't know it.
One quick way to solve/ correction mask the problem is install 460/550 springs. There the bump steer is gone. I can fly over hills , hit dips and I don't feel a thing. That is only because you have immobilized the suspension so you are not getting any toe change.
I run 280 pound long travel morosso springs, the ride is great and yet my suspension is free to soak up road bumps. I also think really heavy sway bars are another bandaid.
Guys I run regularly at 130 mph over rough roads with never a twitch in the steering wheel or the car darting out.
Bump steer can be improved dramatically by just lowering the outer tie rods about 1 inch.
Coleman racing sells a 5/8th bolt and nut plus a few shims and 2 heim joints to replace the outer tie rods.
That alone willl cut the bump steer in half.
 

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Discussion Starter #11
I looked at that site a while ago but I think it is basically about how to use the bump steer gage which is pricy itself and only needed it you are really serious. I have the gage but only use it in the winter when the car is apart.
I will post some other sites tomorrow from my work computer,
Have a nice evening
 

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Norval i totally agree with your discussion thing. On the corvetteforum that we came from there is hardly anything there that is inspiring. You just got those "look at this ebay car", "what colour should i paint my car", " I drove a Z06" type threads. I really dont learn anything from that site anymore, just waste my time there. About the only good thing i have learned would be the hydraboost brakes that you mentioned, the 5 speed transmission swap from a camaro or mustang. That forum has gone to the sh*ts, hopefully this one will replace it and actually be a place for us to come to and learn and discuss things.
 

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Discussion Starter #13
Battsup. I will discuss anything about the corvette you want except the things you already mentioned. I get sick of discussions on what color to paint my calipers too.
There are a few very knowledgable people of the corvette forum that readily discuss bump steer, suspesion or anything performance related. Twin Turbo for one is very knowledgable as is Pete, George, Jim, 427 hot rod , glenn etc etc.
Very good guys.
I like discussions, think I know our cars pretty well and want to get different perspecitves.
 

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Norval...Did you read the slight problem I was experiencing with my newly installed Hydroboost brakes? Not so much a problem as such, but more a quirk. Paul (Hydratech) suggested it has something to do with my routing of the low pressure return lines both to the P/S pump and the assist unit.
I'll let you know how it goes when I get my car back in a couple of days then I can try out his remedies.

Bob
 

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Discussion Starter #15
Brutus I read about your problem and posted about it partly. I will wait to see if Paul solves it. I do have 2 seperate return lines on my hydraboost since I run a nascar pump and seperate resovour. I have experienced what you are saying about shimming the master cylinder too.
I also find that the units are a little grabby for the first few miles when new and even being allowed to sit over the winter but after a little running they stop grabbing and work fine.
Keep in touch Brutus and nice to see you here.
 

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This is all well and good, but what do you think about painting my car? Should it be red?:rolling:

Just Kidding Norvel, welcome from a another '75 owner.
 

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Discussion Starter #17
Rich's 75 Red is a good color but there are lots of other good colors too.
YOu know what they say about guys in a red sport's car.

What is the difference between a porcupine and a guy in a red sports car?
 

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norvalwilhel said:
Rich's 75 Red is a good color but there are lots of other good colors too.
YOu know what they say about guys in a red sport's car.

What is the difference between a porcupine and a guy in a red sports car?
Guys in Red sports car? No, go ahead and tell me.

As for the Porcupine and a guy in a red sports car, I would have to say "they're both little pricks!" How did I do?
 

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Norval...I won't have my car back until tomorrow unfortunately, so I can't relate anything or apply any of the recommendations offered so far. I will be sure to post anything as it happens tho.
I think I have an issue with the timing I have to sort out first tho. Possibly have the distributor one tooth out when I re-installed it so I'll have to start from scratch after I locate TDC. All this with our club's yearly major show coming up this weekend too!
 
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